1. Field of the Invention
The present invention relates to a storage device such as (for example) a disk array device or the like, a storage part for such a storage device, and a dummy unit for such a storage device.
2. Description of the Related Art
In storage devices, for example, large-capacity storage volumes are formed by disposing storage devices such as hard disk drives or the like in the form of an array, and providing these storage volumes to higher devices such as main frames, servers or the like.
Storage devices are modulized together with circuit boards, signal connectors and the like, and a plurality of storage devices are attached inside storage boxes. Inside such storage boxes, the respective storage devices are respectively connected to back boards, and the respective storage devices are respectively connected to control modules via these back boxes.
The respective storage devices are respective heat radiating bodies. Accordingly, the flow of a cooling air draft is created by air intake fans installed inside the storage devices, and the respective storage devices are respectively cooled by supplying this cooling air draft to the respective storage devices. Connectors that are respectively connected to the respective storage devices, and a plurality of exhaust ports that are used to discharge the cooling air drafts flowing into the storage boxes, are respectively installed on the back boards.
The number of storage devices that are mounted is not a fixed number; since storage devices are mounted as required, empty slots may be generated inside the storage boxes. If such empty slots are left “as is”, dust adheres to the empty connectors mounted on the back boards; furthermore, the appearance is also poor. Accordingly, dummy modules are mounted in empty slots.
In conventional techniques, air intake ports and connector caps are respectively provided in such dummy modules. External air is taken into the storage box from the air intake ports, and empty connectors and exhaust ports in the back board are covered with these connector caps (Japanese Patent Application Laid-Open No. 11-145658).
In the technique described in Japanese Patent Application Laid-Open No. 11-145658, the amount of the cooling air draft that flows around the dummy modules is reduced by covering some or all of the exhaust ports in the back board with connector caps. As a result, in the prior art, an increase in the cooling air draft that flows around the storage devices is achieved.
However, in this prior art, a construction that uniformly lowers the amount of the cooling air draft that flows around the dummy modules is used; no consideration is given to the cooling of the boundary portions where dummy modules and storage devices are adjacent. When the amount of the cooling air draft that flows around the dummy modules is lowered, the amount of the cooling draft that flows around the storage devices that are adjacent to these dummy modules also drops, so that a sufficient cooling air draft cannot be supplied to storage devices that are positioned in these boundary portions. Accordingly, in order to supply a sufficient cooling air draft to the storage devices positioned in these boundary portions as well, it is necessary to improve the performance of the cooling fans or the like, so that the energy consumption is increased.
On the other hand, in cases where the amount of the cooling air draft that flows around the dummy modules is set at an amount that is comparable to the amount of the cooling air draft that flows around the storage devices, the overall amount of the cooling air draft is increased by an amount equal to the cooling air draft that is supplied to dummy modules that do not require cooling, so that the cooling efficiency drops.